OBJECTIVE To evaluate the efficacy and safety of sacituzumab tirumotecan combined with bevacizumab for the treatment of human epidermal growth factor receptor 2-negative （HER2－） breast cancer with brain metastases.METHODS Clinical data of 90 patients with HER2－ breast cancer with brain metastases treated at the First Affiliated Hospital of Nanyang Medical College from December 2024 to November 2025 were retrospectively collected. According to the treatment regimens， the patients were divided into a control group （ n ＝55） and an experimental group （ n ＝35）. Patients in the experimental group received sacituzumab tirumotecan combined with bevacizumab， whereas those in the control group received conventional systemic therapy， including albumin-bound paclitaxel-based regimens， capecitabine-based regimens， or gemcitabine/vinorelbine combined with platinum-based regimens. Short-term efficacy， progression-free survival （PFS）， brain metastasis-related efficacy， adverse events， treatment discontinuation due to adverse events， and treatment-related deaths were compared between the two groups.RESULTS The objective response rate （ORR）， disease control rate， median PFS， intracranial disease control rate， and proportion of patients with improvement in neurological symptoms in the experimental group were significantly higher than in the control group （ P ＜0.05）. Stratified analysis showed that PFS of the experimental group was significantly longer than the control group among patients with Breast-Graded Prognostic Assessment scores ≥2.0 and ＜2.0 （ P ＜0.05）. There were no statistically significant differences in the proportion of patients with glucocorticoid dose reduction/discontinuation， the incidence of adverse events of different grades， or the rate of treatment discontinuation due to adverse events between the two groups （ P ＞0.05）. No treatment-related deaths occurred in either group.CONCLUSIONS Compared with conventional systemic therapy， sacituzumab tirumotecan combined with bevacizumab can improve the ORR and prolong PFS in patients with HER2－ breast cancer with brain metastases， with an overall manageable safety profile.

Objective To investigate the association between intestinal microbiota dysbiosis and colonic polyps,Helicobacter pylori(Hp)infection,and intestinal metaplasia.Methods A total of 200 patients diagnosed with colonic polyps,Hp infection,or both conditions.These patients were classified into three groups:the colonic polyp group(n=90),the Hp infection with intestinal metaplasia group(n=49),and the colonic polyp combined with Hp infection and intestinal metaplasia group(n=61).Additionally,62 individuals who underwent routine health examinations at our hospital during the same period were enrolled as a control group.The study compared gut microbiota imbalances across these groups to investigate the association between intestinal dysbiosis and colonic pol-yps,Hp infection,and the co-occurrence of colonic polyps with Hp-related intestinal metaplasia.Logistic regression analysis was performed to identify risk factors associated with the development of intestinal metaplasia due to Hp infection in patients with colonic polyps.Results Compared to the control group,intestinal flora imbalance was significantly more prevalent in the colorectal polyp group,the Hp infection with intestinal metaplasia group,and the colorectal polyp combined with Hp infection and intestinal metaplasia group(P<0.05).Moreover,intestinal flora imbalance in the colorectal polyp with Hp infection and intestinal metaplasia group was significantly higher than that in both the colorectal polyp group and the Hp infection with intestinal metaplasia group(P<0.05).Regarding exhaled gas levels,H2 and CH4 concentrations were significantly elevated in the groups with colorectal polyps accom-panied by Hp infection and intestinal metaplasia,those with colorectal polyps alone,and those with Hp infection and intestinal metaplasia,compared to the control group(P<0.05).Similarly,exhaled H2S levels were significantly higher in the group with colorectal polyps complicated by Hp infection and intestinal metaplasia than in the control group(P<0.05).Furthermore,exhaled H2 and CH4 levels showed positive correlations with the presence of colorectal polyps,Hp infection with intestinal metaplasia,and colorectal polyps combined with Hp infection and intestinal metaplasia(P<0.05).Exhaled H2S levels were positively correlated with colorectal polyps complicated by Hp infec-tion and intestinal metaplasia(P<0.05).Logistic regression analysis indicated that a history of smoking,atrophic gastritis,peptic ulcer,and intestinal flora imbalance are independent risk factors for Hp infection-associated intesti-nal metaplasia in patients with colorectal polyps(P<0.05).Conclusion Intestinal flora imbalance is associated with colorectal polyps and Hp-induced intestinal metaplasia,suggesting that microbial dysbiosis may represent a potential risk factor for the development of these conditions.

In order to delve into the molecular mechanism underlying the increased pathogenicity of the recombinant Muscovy duck parvovirus(rMDPV)towards Muscovy ducklings,two sub-genom-ic fragments of the rMDPV strain ZW were cloned into the plasmid pBluescript Ⅱ(SK)to gener-ate the recombinant plasmid pZW.A single nucleotide mutation was engineered in the VP3 gene of pZW to discriminate from the parental strain ZW.pZW plasmid-lipid complex was transfected into the chorioallantoic membrane of 11-day-old embryonated Muscovy duck embryos,resulting in res-cue of infectious virus,rZW,carrying the genetic marker.The rescued virus was passaged in 12-day-old embryonated Muscovy duck embryos and exhibited the similar medium embryo lethal dose(ELD50)value and growth curve compared to the parental strain ZW.Both rZW and strain ZW led to 100％mortality in the infection tests performed with 3-day-old Muscovy duckling.Postmortem necropsy revealed a characteristic intestine embolism formed in the rZW-infected ducklings.Taken together,the generation of the infectious clone pZW lays a solid foundation for deciphering the pathogenesis of rMDPV.

Objective:This study aimed to analyze the genetic subtypes and drug resistance transmission characteristics of HIV-1 among the preoperative population in Ningxia from 2018 to 2023, to provide a scientific basis for the prevention and control of the AIDS epidemic.Methods:Plasma samples and demographic information of HIV/AIDS patients receiving antiviral treatment in Ningxia from 2018 to 2023 were collected. Blood samples with a viral loads >200 copies/ml from preoperative testing were amplified, sequenced, and subjected to genotypic resistance testing to analyze their genetic subtypes and drug resistance characteristics. The TN93 model in MEGA11 software was used to calculate the genetic distance between each pair of all sequences, and a molecular transmission network was constructed in Cytoscape 3.10.0 with 1.9% as the genetic threshold.Results:Among 101 preoperative HIV/AIDS patients, CRF07_BC and CRF01_AE were the predominant subtypes. The majority were male (85.15%, 86/101), aged 41-60 years (45.54%, 46/101), residing in Yinchuan city (61.39%, 62/101), and infected via heterosexual transmission (71.29%, 72/101), with most cases being late-detected. Of 39 drug-resistant sequences, resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) alone (18.81%, 19/101) and dual resistance to nucleoside reverse transcriptase inhibitors (NRTIs)-NNRTIs (13.86%, 14/101) were most common. Among 44 sequences forming 13 transmission clusters, nine clusters harbored drug-resistant mutations. Four subtypes entered the molecular network, primarily involving heterosexual transmission, individuals with junior high school education or below, and men aged≥50 years.Conclusions:From 2018 to 2023, the preoperative HIV/AIDS patients had diversified genetic subtypes, with higher rates of overall drug resistance and late detection, stronger drug resistance and higher mortality rate. Strengthening molecular epidemiological research and developing targeted screening strategies are critical to improve early detection and reduce transmission risks.

Objective To investigate the association between intestinal microbiota dysbiosis and colonic polyps,Helicobacter pylori(Hp)infection,and intestinal metaplasia.Methods A total of 200 patients diagnosed with colonic polyps,Hp infection,or both conditions.These patients were classified into three groups:the colonic polyp group(n=90),the Hp infection with intestinal metaplasia group(n=49),and the colonic polyp combined with Hp infection and intestinal metaplasia group(n=61).Additionally,62 individuals who underwent routine health examinations at our hospital during the same period were enrolled as a control group.The study compared gut microbiota imbalances across these groups to investigate the association between intestinal dysbiosis and colonic pol-yps,Hp infection,and the co-occurrence of colonic polyps with Hp-related intestinal metaplasia.Logistic regression analysis was performed to identify risk factors associated with the development of intestinal metaplasia due to Hp infection in patients with colonic polyps.Results Compared to the control group,intestinal flora imbalance was significantly more prevalent in the colorectal polyp group,the Hp infection with intestinal metaplasia group,and the colorectal polyp combined with Hp infection and intestinal metaplasia group(P<0.05).Moreover,intestinal flora imbalance in the colorectal polyp with Hp infection and intestinal metaplasia group was significantly higher than that in both the colorectal polyp group and the Hp infection with intestinal metaplasia group(P<0.05).Regarding exhaled gas levels,H2 and CH4 concentrations were significantly elevated in the groups with colorectal polyps accom-panied by Hp infection and intestinal metaplasia,those with colorectal polyps alone,and those with Hp infection and intestinal metaplasia,compared to the control group(P<0.05).Similarly,exhaled H2S levels were significantly higher in the group with colorectal polyps complicated by Hp infection and intestinal metaplasia than in the control group(P<0.05).Furthermore,exhaled H2 and CH4 levels showed positive correlations with the presence of colorectal polyps,Hp infection with intestinal metaplasia,and colorectal polyps combined with Hp infection and intestinal metaplasia(P<0.05).Exhaled H2S levels were positively correlated with colorectal polyps complicated by Hp infec-tion and intestinal metaplasia(P<0.05).Logistic regression analysis indicated that a history of smoking,atrophic gastritis,peptic ulcer,and intestinal flora imbalance are independent risk factors for Hp infection-associated intesti-nal metaplasia in patients with colorectal polyps(P<0.05).Conclusion Intestinal flora imbalance is associated with colorectal polyps and Hp-induced intestinal metaplasia,suggesting that microbial dysbiosis may represent a potential risk factor for the development of these conditions.

Objective:To investigate how age and nail-tract volumetric bone mineral density (vBMD) are associated with postoperative mechanical performance of proximal femoral nail anti-rotation (PFNA-Ⅱ) fixation for geriatric intertrochanteric fractures using a finite-element analysis.Methods:Fifteen elderly patients with intertrochanteric fracture of the femur were selected for this study. They were 11 females and 4 males and divided into 5 groups based on their ages ( n=3): 55-year-old, 65-year-old, 75-year-old, 85-year-old, and 95-year-old groups. After three-dimensional models of the proximal femur were constructed using the preoperative CT data of their healthy contralateral hip, 31-A1.2 fractures of the AO/OTA type were created and PFNA-Ⅱ fixations simulated. Two loading schemes were created: graded quasi-static axial loads (700 N, 1,400 N, 2,100 N, and 2,800 N) were applied to compute equivalent plastic strain volumes in the femoral head region; displacement-controlled loading was applied to failure to derive load-displacement curves for stiffness and the maximum failure load. Nail-tract vBMD and regional hip vBMDs were measured by quantitative CT. Pearson correlation analysis was conducted to investigate the associations of age and nail-tract vBMD with the aforementioned mechanical indicators. Results:Under the same load, compared with the 55-year-old, 65-year-old, and 75-year-old groups, the plastic strain unit volumes of the fracture models in the 85-year-old and 95-year-old groups increased significantly. Under a load of 700 N, no plastic strain was observed in the fracture models in the 55-year-old, 65-year-old, and 75-year-old groups, while an average plastic strain of approximately 50 mm 3 was observed in the fracture models in the 85-year-old group. Under a load of 2,800 N, the high strain areas in the fracture models in the 85-year-old and 95-year-old groups were mainly concentrated at the tip of the head nail and the junction between the head nail and the main nail. Load-displacement curves showed a marked reduction in the failure load in patients aged ≥85 years. Under loads of 1,400 N, 2,100 N, and 2,800 N, there was a strong association between the nail-tract vBMD and the volume of the plastic strain unit ( r=-0.82, -0.88, -0.89, respectively), which was stronger than those for total-hip vBMD. Conclusions:Finite-element analysis indicates that age and nail-tract vBMD are closely related to local plastic strain and overall stiffness of the proximal femur after PFNA-Ⅱ fixation for the geriatric intertrochanteric fractures. Patients aged ≥85 years old are more prone to plastic yielding, which compromises fixation stability.

In order to delve into the molecular mechanism underlying the increased pathogenicity of the recombinant Muscovy duck parvovirus(rMDPV)towards Muscovy ducklings,two sub-genom-ic fragments of the rMDPV strain ZW were cloned into the plasmid pBluescript Ⅱ(SK)to gener-ate the recombinant plasmid pZW.A single nucleotide mutation was engineered in the VP3 gene of pZW to discriminate from the parental strain ZW.pZW plasmid-lipid complex was transfected into the chorioallantoic membrane of 11-day-old embryonated Muscovy duck embryos,resulting in res-cue of infectious virus,rZW,carrying the genetic marker.The rescued virus was passaged in 12-day-old embryonated Muscovy duck embryos and exhibited the similar medium embryo lethal dose(ELD50)value and growth curve compared to the parental strain ZW.Both rZW and strain ZW led to 100％mortality in the infection tests performed with 3-day-old Muscovy duckling.Postmortem necropsy revealed a characteristic intestine embolism formed in the rZW-infected ducklings.Taken together,the generation of the infectious clone pZW lays a solid foundation for deciphering the pathogenesis of rMDPV.

Objective:This study aimed to analyze the genetic subtypes and drug resistance transmission characteristics of HIV-1 among the preoperative population in Ningxia from 2018 to 2023, to provide a scientific basis for the prevention and control of the AIDS epidemic.Methods:Plasma samples and demographic information of HIV/AIDS patients receiving antiviral treatment in Ningxia from 2018 to 2023 were collected. Blood samples with a viral loads >200 copies/ml from preoperative testing were amplified, sequenced, and subjected to genotypic resistance testing to analyze their genetic subtypes and drug resistance characteristics. The TN93 model in MEGA11 software was used to calculate the genetic distance between each pair of all sequences, and a molecular transmission network was constructed in Cytoscape 3.10.0 with 1.9% as the genetic threshold.Results:Among 101 preoperative HIV/AIDS patients, CRF07_BC and CRF01_AE were the predominant subtypes. The majority were male (85.15%, 86/101), aged 41-60 years (45.54%, 46/101), residing in Yinchuan city (61.39%, 62/101), and infected via heterosexual transmission (71.29%, 72/101), with most cases being late-detected. Of 39 drug-resistant sequences, resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs) alone (18.81%, 19/101) and dual resistance to nucleoside reverse transcriptase inhibitors (NRTIs)-NNRTIs (13.86%, 14/101) were most common. Among 44 sequences forming 13 transmission clusters, nine clusters harbored drug-resistant mutations. Four subtypes entered the molecular network, primarily involving heterosexual transmission, individuals with junior high school education or below, and men aged≥50 years.Conclusions:From 2018 to 2023, the preoperative HIV/AIDS patients had diversified genetic subtypes, with higher rates of overall drug resistance and late detection, stronger drug resistance and higher mortality rate. Strengthening molecular epidemiological research and developing targeted screening strategies are critical to improve early detection and reduce transmission risks.

Objective:To investigate how age and nail-tract volumetric bone mineral density (vBMD) are associated with postoperative mechanical performance of proximal femoral nail anti-rotation (PFNA-Ⅱ) fixation for geriatric intertrochanteric fractures using a finite-element analysis.Methods:Fifteen elderly patients with intertrochanteric fracture of the femur were selected for this study. They were 11 females and 4 males and divided into 5 groups based on their ages ( n=3): 55-year-old, 65-year-old, 75-year-old, 85-year-old, and 95-year-old groups. After three-dimensional models of the proximal femur were constructed using the preoperative CT data of their healthy contralateral hip, 31-A1.2 fractures of the AO/OTA type were created and PFNA-Ⅱ fixations simulated. Two loading schemes were created: graded quasi-static axial loads (700 N, 1,400 N, 2,100 N, and 2,800 N) were applied to compute equivalent plastic strain volumes in the femoral head region; displacement-controlled loading was applied to failure to derive load-displacement curves for stiffness and the maximum failure load. Nail-tract vBMD and regional hip vBMDs were measured by quantitative CT. Pearson correlation analysis was conducted to investigate the associations of age and nail-tract vBMD with the aforementioned mechanical indicators. Results:Under the same load, compared with the 55-year-old, 65-year-old, and 75-year-old groups, the plastic strain unit volumes of the fracture models in the 85-year-old and 95-year-old groups increased significantly. Under a load of 700 N, no plastic strain was observed in the fracture models in the 55-year-old, 65-year-old, and 75-year-old groups, while an average plastic strain of approximately 50 mm 3 was observed in the fracture models in the 85-year-old group. Under a load of 2,800 N, the high strain areas in the fracture models in the 85-year-old and 95-year-old groups were mainly concentrated at the tip of the head nail and the junction between the head nail and the main nail. Load-displacement curves showed a marked reduction in the failure load in patients aged ≥85 years. Under loads of 1,400 N, 2,100 N, and 2,800 N, there was a strong association between the nail-tract vBMD and the volume of the plastic strain unit ( r=-0.82, -0.88, -0.89, respectively), which was stronger than those for total-hip vBMD. Conclusions:Finite-element analysis indicates that age and nail-tract vBMD are closely related to local plastic strain and overall stiffness of the proximal femur after PFNA-Ⅱ fixation for the geriatric intertrochanteric fractures. Patients aged ≥85 years old are more prone to plastic yielding, which compromises fixation stability.

Objective:To explore the correlation between hip muscle factors measured with CT imaging and recovery of independent mobility within 1 year after surgery in elderly patients with hip fractures.Methods:A prospective cohort study was conducted on the clinical data of 680 elderly patients with hip fractures admitted to Beijing Jishuitan Hospital of Capital Medical University from November 2018 to December 2019. The patients were assigned to dependent group and assistant group according to whether they regained pre-injury independent mobility within 1 year after surgery. Gender, age, body mass index, personal history, living habits, past diseases, Charlson comorbidity index, laboratory test indicators, fracture types, anesthesia types, surgical methods, rehabilitation training, time from injury to surgery, and hip muscle parameters in both groups were recorded. OsiriX software was employed in the measurement of the hip muscles to measure the muscle area and density of the gluteus maximus and gluteus medius/minimus on CT images, and the average values were calculated as hip muscle area and density. Then the variables of hip muscle area and density were converted seperately to gender-normalized Z-scores, and were divided into high-area group ( Z≥0) and low-area group ( Z<0), and high-density group ( Z≥0) and low-density group ( Z<0) respectively. Observable variables were primarily analyzed using univariate analysis between the independent group and assistant group. Those variables with statistically significant differences in the univariate analysis or would potentially affect mobility recovery according to previous researches although there were no statistical significance were included in a multivariate Logistic regression analysis. Three Logistic regression models were designed (Model 1 uncorrected, Model 2 corrected for gender, age and body mass index, Model 3 corrected for variables in Model 2 and other variables included after above-mentioned analysis) to analyze whether muscle parameters were risk factors for recovery of independent mobility. Additionally, generalized estimating equations were used for repeated measurement to analyze the correlation between hip muscle area and recovery of independent mobility after surgery. Results:Compared to the assistant group, the independent group were younger in age, with lower rate of living alone, being housebound, cognitive impairment, and Charlson comorbidity index, lower level of hemoglobin and albumin, higher rate of femoral neck fractures, lower rate of internal fixation, shorter time from injury to surgery, larger hip muscle area, and higher hip muscle density ( P<0.05 or 0.01). Multivariate Logistic regression analysis showed that, in the fully corrected Model 3, only hip muscle area remained significantly correlated with recovery of independent mobility ( P<0.05), while no significant difference was found between the high-density group and low-density group ( P>0.05). In the repeated measurement, patients in the high-area group were 1.84 times more likely to restore independent mobility than those in the low-area group ( OR=1.84, 95% CI 1.33, 2.53, P<0.01). Conclusions:Hip muscle area measured with CT imaging is closely correlated to the recovery of independent mobility within 1 year after surgery in elderly patients with hip fractures. Moreover, larger hip muscle area indicates a larger likelihood of recovery of independent mobility.